Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of unrecognized tax benefits.

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Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Income Taxes (Detail) - USD ($) $ in Thousands	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)	$ 1,937	$ 119	$ 4,325	$ 118
Unrecognized tax benefits	5,500		5,500		$ 5,300
Expected change in unrecognized tax benefits	$ 3,500		$ 3,500
Maximum
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)				$ 100